UK Gas Engineering Industry Statistics [2026]

The UK Gas Engineering Industry at a Glance

Gas engineering is one of the largest skilled trades sectors in the UK. The industry encompasses domestic boiler installation and servicing, commercial gas maintenance, gas safety certification, and increasingly, the crossover into low-carbon heating technologies.

Key statistics for the UK gas engineering industry in 2025/2026:

Gas Safe registered engineers: Approximately 115,000–120,000 registered individuals and businesses as of 2025
Annual boiler installations: Approximately 1.7–1.8 million new boilers installed per year in the UK (domestic and commercial combined)
UK gas boiler stock: An estimated 24–25 million gas-fired boilers currently in operation across UK homes and businesses
Gas heating prevalence: Approximately 85% of UK homes are connected to the gas grid; 78% use gas for primary heating
Annual boiler service market: An estimated 12–14 million domestic boiler services per year across the UK
Gas industry revenue: The domestic gas servicing, installation, and maintenance sector generates approximately £8–12 billion in revenue annually

Number of Gas Safe Registered Engineers

Gas Safe Register publishes annual statistics on registered businesses and individuals. As of 2025:

Approximately 115,000–120,000 individuals hold Gas Safe registration
Registered businesses number approximately 45,000–50,000 (including sole traders, small businesses, and larger contractors)
The number of registered engineers has declined modestly over the past decade, from a peak of around 130,000, reflecting an aging workforce and slower apprenticeship intake
Approximately 25–30% of Gas Safe engineers are in the South East and London — reflecting both population density and the higher cost of gas work in these areas driving more formal registration

The declining number of Gas Safe engineers relative to demand is one reason gas engineering remains a well-paid trade. Demand for gas maintenance is broadly static (reflecting the existing stock), while supply of qualified engineers is gradually tightening.

Boiler Installation Market

The UK boiler replacement market is driven primarily by the failure or end-of-life of existing units rather than new build. Key market dynamics:

Average boiler lifespan: 10–15 years, with many units replaced at 12–15 years
New build: Approximately 200,000–250,000 new homes completed per year, a fraction of which use gas boilers (down from previous levels as Part L regulations take effect)
Replacement market: The dominant driver — approximately 1.4–1.6 million replacement boiler installations per year
Average installation value: £1,800–£3,500 for a standard domestic combi replacement, with the market weighted toward the £2,000–£2,800 range for mid-range boilers (Worcester Bosch, Vaillant) and basic installation
Market concentration: No single contractor dominates; the market is fragmented across thousands of small and medium-sized businesses, with British Gas having the largest single share through its HomeCare subscription model

Industry Trends

Several trends are reshaping the UK gas engineering industry through 2026 and beyond:

Energy transition: Government policy targets phase-out of new gas boilers in new homes (already in effect via Part L) and ultimately in existing homes. The Future Homes Standard and Clean Heat Market Mechanism are creating gradual shift toward heat pumps, though the timeline is contested and the existing boiler stock will require servicing for decades
Heat pump growth: Air source heat pump installations have grown from around 50,000/year in 2020 to an estimated 100,000–120,000 per year in 2025. Well below the government's targets but a fast-growing segment for MCS-certified engineers
Smart controls: Smart thermostat penetration has grown rapidly — approximately 35–40% of UK homes have a smart thermostat as of 2025, up from ~15% in 2018. This drives demand for engineer-installed controls and creates recurring customer relationships through app-connected systems
Workforce aging: The average age of a Gas Safe engineer is estimated at 43–45, with a significant proportion expected to retire in the next 10–15 years. This will tighten supply of qualified engineers further

What the Data Means for Gas Engineering Businesses

For gas engineering business owners, the industry data points to a nuanced outlook:

The existing boiler servicing and maintenance market (12+ million services per year) will remain substantial for the next 15–20 years regardless of policy changes. The gas boiler stock cannot be replaced overnight
The new installation market faces genuine long-term pressure from policy and changing technology — but the pace of transition is much slower than headline targets suggest
Qualification diversification — adding heat pump (MCS) and commercial gas qualifications — positions engineers for a larger share of a market in transition
Business model evolution: Annual service contracts, landlord portfolio management, and commercial maintenance provide more resilient recurring income than purely reactive domestic installation work
The workforce shortage benefits established, well-qualified engineers: supply constraints support sustained demand and pricing power

Frequently Asked Questions

We’re happy to answer all your questions.

How many gas engineers are there in the UK?

Approximately 115,000–120,000 individuals are registered with Gas Safe Register as of 2025, representing around 45,000–50,000 registered businesses. The total has been declining modestly from a peak of around 130,000, reflecting an aging workforce.

How many boilers are installed in the UK each year?

Approximately 1.7–1.8 million boilers are installed annually across domestic and commercial properties. The majority (1.4–1.6 million) are replacement installations — end-of-life units in existing properties rather than new builds.

Is gas engineering in decline due to heat pumps?

Not in the short to medium term. The UK has approximately 24–25 million gas boilers in existing properties — a stock that requires servicing and will see natural replacement for 20+ years regardless of policy. Heat pump adoption is growing but represents a small fraction of heating installations. Gas engineering businesses have time to adapt while maintaining strong existing work.

What percentage of UK homes use gas for heating?

Approximately 78–85% of UK homes use gas as their primary heating source, one of the highest proportions in Europe. Reducing this to near-zero would be an enormous infrastructure challenge taking decades — supporting long-term demand for gas engineers even as new installations face policy pressure.

How is the gas engineering workforce changing?

The workforce is aging — estimated average age of 43–45 — with significant retirement expected over the next 10–15 years. Apprenticeship intake has not kept pace with attrition. This creates tightening supply that supports earnings for well-qualified engineers. Businesses that invest in apprentice training now are building a competitive advantage for the future.